Scientists have finally solved the mystery of Earth’s inner core. For the first time researchers from the University of Illinois (UI) and Nanjing University in China, found an inner core lying beneath the innermost core of the Earth when they projected seismic waves used in ultrasound to explore the planet’s deepest areas.
Xiaodong Song, a professor of geology at the UI said “Even though the inner core is small – smaller than the moon – it has some really interesting features. It may tell us about how our planet formed, its history and other dynamic processes of the Earth. It shapes our understanding of what’s going on deep inside the Earth”.
Earlier it was believed that the Earth’s entire inner core is made up of iron giving an appearance of a huge iron ball at the centre. However, researchers penetrated Earth’s surface using seismic waves and analysed the collected data. The results were astonishing. The earthquake is like a hammer striking a bell; much like a listener hears the clear tone that resonates after the bell strike, seismic sensors collect a coherent signal in the earthquake’s coda.
This indicates that inner core has much complex region than thought previously. They found two distinct areas in the center. Iron crystals in both the cores are aligned in different directions, another proof of the finding. Outer core has metal crystals aligned along north-south direction while they are aligned along east-west direction in the inner core. Some scientists have also noticed the change in seismic waves while it travelled through both the cores, however, no one till date was able to interpret the orientation of iron crystals precisely.
Scientists believed that this finding can help revealing the earth’s history of evolution. Change in orientation must be a result of something strange and massive that happened inside the core. It can tell us about all the changes that our planet went through over several years and how it evolved eventually.